package com.zgh.util;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class DayLength {
	public static double dayLength(String startTime,String overTime) {
		SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        SimpleDateFormat format2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date2 = null;
        Date date = null;
		try {
			date2 = format.parse(overTime);
			date = format.parse(startTime);
		} catch (ParseException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		 Calendar cal1 = Calendar.getInstance();
	        cal1.setTime(date);
	        Calendar cal2 = Calendar.getInstance();
	        cal2.setTime(date2);
	        int day1= cal1.get(Calendar.DAY_OF_YEAR);
	        int day2 = cal2.get(Calendar.DAY_OF_YEAR);
	        int year1 = cal1.get(Calendar.YEAR);
	        int year2 = cal2.get(Calendar.YEAR);
	        if(year1 != year2)   //同一年
	        {
	            int timeDistance = 0 ;
	            for(int i = year1 ; i < year2 ; i ++)
	            {
	                if(i%4==0 && i%100!=0 || i%400==0)    //闰年            
	                {
	                    timeDistance += 366;
	                }
	                else    //不是闰年
	                {
	                    timeDistance += 365;
	                }
	            }
	            return timeDistance + (day2-day1) ;
	        }
	        else    //不同年
	        {
	            System.out.println("判断day2 - day1 : " + (day2-day1));
	            return day2-day1;
	        }
		}

}
